Refrigeration apparatus



` Feb. 9, 1943. R. H. TULL REFRIGRATION APPARATUS Filed sept. 26, 1940 2sheets-sheet 1 F/G.- l..

INVENTOR PoBER-r H. Tuu.

WTNE ESZ Mw Feb. 9, 1943. R'. H. 'ru|.|

REFRIGERATION APPARATUS Filed Sept. 26, 1940 2 Sheets-Sheet 2 INVENTORROBERT H. TULA.

ATTOR Y lFIG. 5.

Patente Feb. 9, i943 'Armes BEFRIGERATION APPRATUS PennsylvaniaApplication September 26, 1940, Serial No. 358,433

9 Claims.

This invention relates to refrigeration apparatus and more especially tolarge refrigerator cabinets.

One object of the invention is to provide a simple construction forlarge refrigerators, such as display cases.

Another object is to provide a refrigerator of the type described whichis cooled to a substantially uniform temperature throughoutV by a singlecooling element which does not require a separate drip collector.

A further object is to provide refrigerators of the type described whichare adapted for maintaining high humidities in the cabinets.

These and other objects are eiected by the invention as will be apparentfrom the following description and claims taken in connection with theaccompanying drawings, forming a part of this application, in which:

Fig. 1 is a sectional view in perspective of the refrigerator of thisinvention, taken on the line I-I of Fig. 2;

Fig. 2 is a partial section taken on the line of the front wall I2 ofthe cabinet and is slanted rearwardly to provide a view of the contentsof the cabinet. The upper portion of the rear wall i3 is slopedsimilarly and provided with tripleglazed doors It, which slide past oneanother to afford access to the interior of the upper portionof thecabinet. The lower portion of the rear wall I3 is provided with twodoors I5 which provide access to the lower portion of the cabinet.V

The cabinet is divided into an upper food storage chamber I6 and a lowerfood storage chamber I'I by a sloping grid I8 resting on supports I9secured to the front wall I2 and the rear wall I3. A flat cooling unit2| is located in the lower food chamber I'I adjacent-but spaced from thefront wall I2 of the cabinet I0 and extends from the bottom of thechamber I'I to nearly the top thereof and from one end of the chamber I1to nearly the opposite end thereof. The cooling unit 2| comprises aseries of parallel and spacedapart metal strips 23 standing on end and arefrigerant-carrying tube 2l passed back and forth through registeringholes' in the strips 23. The tube 24 may be supplied with refrigerantfrom a source such asa compressor-condenser unit (not shown in thedrawings). A horizontal baille 22 is secured to the upper edge of thecooling unit and extends to wall I2, adjacent thereto to form a confinedair passage 25 together with the cooling unit 2|, the wall I2, and aportion of the bot` tom wall 30 of the lower food chamber Il.

An air duct 26 is located adjacent the upper wall on the interior of thecabinet and occupies the entire area of this wall. The air duct 26 isprovided with openings 21 on its lower surface which communicate withthe upper chamber I6.

A false end wall 28 is located adjacent the end wall 29 of the cabinet||l to provide an air duct 3| with said end wall 29 which air duct 3|communicates with the upper air duct 26. A circular opening 32 isprovided near the bottom of the false end wall 28 and adjacent thecooling unit 2 I, and a baille 33 is located diagonally across thecorner of the lower food storage chamber Il which together with anextension 2D of the horizontal baille 22, provides communication betweenthe circular opening 32 and the air passage 25 adjacent the cooling unit2|. A housing 34 carrying a motor 36 is secured in the circular opening32 and a fan 3l is secured to the shaft of the motor 36. The fan 3l isadapted to draw air through the air ducts 3| and 26 from the 'upperportion of the upper food storage chamber i6 and pass it to the airpassage 25 adjacent the cooling unit 2|, the air thereafter passingthrough the cooling unit 2 -The particular arrangement of the strips ofmetal 23 of the cooling unit 2| and the direction of air flow in thepassage 25 is such as to force the air circulated by the fan 3l throughthe cooling unit 2| in a path which does not permit portions of the airto remain in prolonged contact with any of the cooling surfaces of thecooling unit 2|. Prolonged contact of portionsof the air with thecooling surfaces of the cooling unit would chill these portions of theair excessively thereby causing the moisture in these portions of air tocondense and deposit on the cooling unit 2|. Such action is not desiredin a refrigerated cabinet of this nature because it is essential thatall moisture is retained in the air as far as possible to preserve thehumidity of the air. To

`minimize the length of time that the air is in contact with the coolingunit 2|, the latter is relatively thin, a thickness of about one andonehalf inches for a cooling unit about five feet in length having beenfound suitable. The openings 21 in the upper air duct 26 areproportioned toprovide a substantially uniform air iiqw through thecabinet I0 and for this reason are more numerous at the portions of theduct 26 farthest removed from the fan 3l.

The cooling unit 2| keeps the display case at a substantially uniformtemperature. The chilled air from the central and lower portion of thecooling unit 2| sweeps through the lower food storage chamber I1,-absorbs heat therefrom and passes upwardly through the upper foodstorage chamber I6. The air from the upper portion of the cooling unit2| flows more directly to the upper food storage chamber I5 withoutabsorbing much heat from the lower food storage chamber I1 and is thusavailable for absorbing heat from the upper food storage chamber I6.

To aid the passage of the air through .the cooling unit as abovedescribed, a cellular louver 35 comprising crossed louver boards 40 isprovided at the entrance of the air passage 25. The louver 35 dampenstlie eddy currents-ordinarily found in air flowing in irregular airducts and the air swirls caused by the fan 31 so that the air passingthrough the cooling unit passes therethrough in` quiescent layers. l

The cooling unit 2| is -maintained at a temperature suiiiciently high toprevent the accumulation of frost thereon and is of large area in orderto cool large quantities of the aixl passing through it substantiallyuniformly bya few degrees of temperature rather than by cooling asmaller quantity of air through a larger temperature range. This againavoids cooling porytions of the air in the cabinet to a temperature lowenough Ato cause precipitation of substantial quantities of the watervapor in the air.

The rate of air flow through the two food storage chambers |6 and fromthe-cooling unit 2| to the upper air duct 26 is about 15 feet per minuteand is maintained at this low value to avoid the rapid sweeping of airover the foods displayed in the cabinet as this would tend to dehydratethe food. The current of air is furthermore directed upwardly throughthe food storage chambers so that the .trays and platters on which moistfoods are ordinarily displayed act as a, wind break for the foods. Ithas been found that in actual practice a humidity of 85 per cent can bemaintained in the cabinet.

The lower portion of the lower 'food storage chamber is of leak-proofconstruction and the openings for the doors I5 are elevated above thebottom of the chamber I1 to prevent escape of the moisture condensed bythe cooling unit 23. A drain 38 is also provided in the bottom of thelower food storage chamber I1 to carry ofi the moisture collectedthereon. `This construction makes the use of a drip collectorunnecessary.

A platform for supporting the articles to be refrigerated is located inthe lower food storage chamber, which platform comprises girders 4|resting on the bottom 39 of the lower food stor-l age chamber and crosspieces 42 placed across the girders 4|.

It will be observed that this invention provides a large refrigerator ofthe display case type, which refrigerator is of simple construction andmaintains a substantially uniform temperature and high humidity for thepreservation of foods.

While I have shown my invention in but one 1. In a refrigerator, thecombination of an insulated cabinet, the length of which exceeds itsbreadth; a foraminated partition in said cabinet dividing the same intoan upper and aflower food storage chamber; a nat cooling unit adjacentbut spaced from one of the longitudinal walls of the lower food 'storagechamber, said cooling unit being substantially commensurate with saidwall, said cooling .unit having air passages therein substantially atright angles to the flat portion thereof; a substantially horizontalballe at the upper edge'of the cooling unit extending to the walladjacent thereto to define an air duct t0- gether with said wall, saidcooling unit, and av storage compartment to cool said compartments'substantially uniformly.

2. In a refrigerator, the combination of an insulated cabinet, thelength of which exceeds its breadth; a foraminated partition in saidcabinet dividing the same into an upper and a lower food storagechamber; a flat cooling unit adjacent but spaced from one of thelongitudinal walls of the lower food storage chamber, said cooling unitbeing substantially commensurate with said wall, said cooling unithaving air passages therein substantially at right angles to the flatportion thereof; a substantially horizontal baille at the upper edge ofthe cooling unit extending to the wall adjacent thereto to define an airduct t0- gether with said wall, said cooling unit and a portion ofthebottom of said cabinet; a louver comprising a series of parallelbaille plates in said air duct to suppress eddies of air in said duct; asecond duct adjacent the upper interior wall of said cabinet andextending substantially the full length thereof, said duct having aplurality of openings distributed throughout its length andcommunicating with the upper food storage chamber; and means forforcibly conducting air from said second duct to said flrst-named duct,the air thereafter passing substantially horizontally through the airpassages of the cooling unit, the air thereafter flowing upwardly fromthe lower to the upper food storage compartment.

3. In a refrigerator, the combination of an insulated cabinet, thelength of which exceeds its breadth, said cabinet defining a foodAstorage chamber, a fiat cooling unit adjacent to but spaced from one ofthe longitudinal walls of the cabinet and extending along substantiallythe full length of said wall, said cooling unit having its lower edgeadjacent'the bottom of said cabinet and its upper edge extendingupwardly in said food storage chamber to at least one-third the heightthereof, said cooling unit having air passages therein at right anglesto the flat portion thereof, a substantially horizontal baille at theupper edge of the cooling unit extending to the wall of the cabinetadjacent thereto, a duct adjacent the upper interior wall of saidcabinet and extending substantially along the full length thereof, saidduct having a plurality of openings distributed throughoutits length andcommunieating with the' food storage chamber, a second ductcommunicating with said rst-named duct and vwith the space between thecooling unit and the wall adjacent thereto, means for forciblycirculating air through said second duct in. a direc tion toward saidspace whereby said air passes through the air passages of the coolingunit substantially at right angles to the flat side thereof and flowsthrough said food storage chamber to maintain the temperature of the topand bottom portions thereof substantially uniform.

4. In a refrigerator, the combination of an insulated cabinet, thelength of which exceeds its breadth, a foraminated partition in saidcabinet dividing the same into an upper and a lower food storagechamber, a flat cooling unit adjacent but spaced from one of thelongitudinal walls of the lower food storage chamber, said cooling unitcomprising a series of spaced-apart thin metal strips with the flatsides facing one another, said strips extending substantially from thebottom to adjacent the top of the lower food storage chamber, and theseries of spaced-apart strips extending along at least three-quarters ofthe length of said lower food storage compartment, a substantiallyhorizontal baffle at the upper edges of said spaced-apart strips andextending to the vertical wall adjacent the cooling unit, a ductadjacent the upper interior wall of said cabinet and extendingsubstantially along the full length thereof, said duct having aplurality of openings distributed throughout its length andcommunicating with the food storage chamber, a second duct communicatingwith said first-named duct and with the space between the cooling unitand the wall adjacent thereto at one end of said space, and means forforcibly circulating air from said duct at the upper portionv of thecabinet through said second duct, the air thereafter passing through atleast a portion of the space between the cooling unit and the walladjacent thereto and thereafter between the thin strips of metal, thethin strips of metal guiding fsaid air at right angles to its directionof travel through said space through the cooling unit and into the lowerfood storage chamber, the air thereafter passing upwardly through theforaminated partition into the upper food storage chamber towards theopenings in the duct adjacent the upper wall of said upper food storagechamber.

5. In a display case, the combination of an insulated cabinet, thelength of which exceeds its. breadth; a foraminated partition in saidcabinet to divide the same into an upper and a lower food passages ofthe cooling storage chamber; an inclined window in the upper foodstorage chamber; an access opening and a door for the same in the lowerfood storage chamber, said access opening being elevated above thebottom of said cabinet; aflat cooling unit adjacent but spaced from oneof the longitudinal walls of the cabinet and extending alongsubstantially the full length and height of said wall, said cooling unithaving air passages therein substantially at right angles to the flatsurface thereof; a substantially horizontal baille at the upper edge ofthe cooling unit and extending to the Wall adjacent thereto to define anair 'duct together with said wall, cooling unit, and a portion of thebase of the cabinet; a second duct adjacent the upper interior wall ofsaid cabinet and extending substantially thereof, said duct having-aplurality of openings distributed through its length and communicatingwith the upper food storage chamber; a third duct communicating with theduct in the upper portion of the cabinet and the air duct adjacent thecooling unit; means for forcibly'circulating along the full length` airthrough said second duct towards said firstnamed duct behind the coolingunit; and a drain in the bottom wall of the cabinet, the lower portionof said cabinet being of leak-proof construc-` between said verticalwall and said cooling unit,

said cooling unit having 'horizontal air passages therethrough, andmeans for moving air from the upper portion of the food storage chamberto said air passage, said air, thereafter, flowing substantiallyhorizontally through the air passages of the cooling unit and into thefood storage chamber.

'7. In a refrigerator, the combination of an insulated cabinet, said`cabinet defining a food storage chamber, a fiat cooling unit at thelower portion of the cabinet and positioned substantially parallel to,but spaced from one of the vertical walls of the cabinet to define anair' duct between said vertical wall and said cooling unit, said coolingunit having horizontal air passages therethrough, and means for movingair from the upper portion of the food storage chamber to said portionof the cabinet and positioned substantially parallel to, but spaced fromone of the vertical walls of the cabinet to define an air duct betweensaid vertical wall and said cooling unit, said cooling unit beingof aheight of at least 1A the interior height of the cabinet and havinghorizontal air passages therethrough, and means for moving air froml'the upper portion of the food storage chamber to said air passage,said air, thereafter, flowing substantially horizontally through the airunit and into the food cooling unit being subfor cooling said foodstorage chamber, said stantially the sole means storage chamber. l

9. In a refrigerator, the combination of an in*- sulated cabinet havingat least one substantially` vertical wall and an upper wall, saidcabinet defining a food-storage chamber, a cooling unit in said cabinetadjacent to said substantially vertical wall of the cabinet andextending substan- `tially the full length of said wall, saidicoolingunit having its lower edge adjacent the bottom of said cabinet andextending upwardly in said food-storage chamber to at least one-thirdthe height thereof, said cooling unit having air passages therein atright angles to said substantial- 1y vertical wall, a duct in saidcabinet adjacent said upper wall and extending substantially the fulllength thereof, said duct having a plurality of openings distributedthroughout its length and

